package org.example;

import java.util.ArrayList;
import java.util.List;

public class Test1 {
    List<List<Integer>> ret;
    List<Integer> path;
    public List<List<Integer>> subsets(int[] nums) {
        ret = new ArrayList<>();
        path = new ArrayList<>();
        dfs(nums,0);
        return ret;
    }

    private void dfs(int[] nums, int index) {
        ret.add(new ArrayList<>(path));
        for (int i = index; i < nums.length; i++) {
            path.add(nums[i]);
            dfs(nums,i + 1);
            path.remove(path.size() - 1);
        }
    }
}
